An increasingly-heard refrain is that if it’s a black gathering, Vice President Joe Biden will show up to lambaste GOP presidential contender Mitt Romney and the GOP. Biden has in recent weeks pounded the GOP at the National Association of Black Journalists convention, and today he will at the NAACP convention. And almost certainly in the coming weeks he will be an even more ubiquitous presence before black and Latino groups. Biden’s assigned role of visible point man for team Obama with minorities raises two tormenting questions for the Obama campaign.

The first — is Biden on the podium at black gatherings part of a well worked out campaign strategy to shield President Obama from the ancient attacks, charges and fears that a too active and visible presence by him at, say, the NAACP convention means that he is showing favoritism toward blacks? The second question is, is Biden the right fit to be the face of the attack on the GOP for black voters? This only becomes an issue because of Biden’s penchant to come out swinging, no matter where the chips may fly. Biden can get down, salty, and even testy. Some of his quips have bordered on the offensive, and have even raised eyebrows and garnered criticisms that he is not always in sync with his boss’s views, or at least the timing of when the president wants to state his positions.

This was certainly the case when Biden appeared to get way out ahead of Obama in endorsing gay marriage. Obama quickly issued his own endorsement of the issue. But would he have done it when he did? Or did Biden’s out front backing of marriage equality force the president to do it, and take heat (and cheers) for it? We’ll have to wait for Obama’s memoirs to get an answer to that. As for as his appearances before black groups, the harder he hits the GOP, the better African-Americans like it.

But the more compelling question is whether the nation’s first black president must move so cautiously and gingerly on the issue of race that it requires his keeping black activists and civil rights groups at arm’s length. He will speak at the National Urban League Convention the end of this month. But the League is not and never has been publicly regarded as an activist civil rights group. It is a group with the avowed historic mission of increasing business and professional opportunities for minorities; thus it’s relatively politically safe. During the first six years of his two administrations, former President George W. Bush was hammered hard for ignoring repeated invitations to speak at the NAACP convention. Yet he spoke at the Urban League convention. Obama’s appearance there will raise no ire or criticism from conservatives.